PNG Compressor
Make PNG screenshots, logos and graphics much smaller with our PNG Compressor. By default it reduces the image to an optimized palette of up to 256 colors with full alpha transparency, using the fewest colors that reach your quality target, then applies maximum zlib compression. Switch palette mode off for a lossless re-compression. A practical tool for designers, developers and site owners.
Frequently asked questions
How does the PNG Compressor reduce file size?
With palette mode on, it converts the image to an indexed PNG with at most 256 colors, chosen by a quantizer that keeps the colors your image actually uses, and applies Floyd-Steinberg dithering to hide banding. The file is then written with zlib level 9. Screenshots, icons and flat graphics often shrink by 50 to 80 percent this way.
What does the quality setting control?
Quality runs from 1 to 100 and defaults to 80. The quantizer uses the lowest number of colors that still reaches this quality, so simple graphics end up with very few colors and small files. Raise it toward 100 when gradients or shadows start to show banding.
What happens when I turn off palette mode?
The image is saved as a full color PNG with adaptive row filtering and maximum zlib compression. This is lossless: every pixel keeps its exact value, and the quality setting has no effect. Savings are smaller, typically 5 to 30 percent, depending on how well the original was compressed.
Is transparency preserved?
Yes. Palette mode supports full alpha transparency in each palette entry, so soft shadows and anti-aliased edges stay smooth. Lossless mode keeps the alpha channel exactly as it was.
Is palette compression suitable for photos?
Photos contain thousands of colors, so reducing them to 256 can cause visible banding in skies and gradients even with dithering. For photos, the JPEG, WebP or AVIF compressors give much smaller files at better quality. Palette PNG works best for user interface screenshots, diagrams, logos and illustrations.
Can I upload other formats than PNG?
Yes, JPEG, GIF, WebP, TIFF and AVIF uploads are accepted as well, and the result is always a PNG file. Animated GIF and WebP files are reduced to their first frame.
Is metadata removed?
Yes, text chunks, EXIF data and embedded color profiles are removed, and colors are converted to sRGB. The EXIF rotation, if present, is applied to the pixels first, so the image keeps its orientation.
What are the size limits?
Each upload can be up to 5 MB. Images wider or taller than 4000 pixels are scaled down to fit within 4000 by 4000 pixels, keeping their aspect ratio.
Why did my PNG barely get smaller?
Images that were already quantized by another optimizer, or very small icons, leave little room for savings. Photos in lossless mode also compress poorly because PNG is designed for exact pixels. Try palette mode with a lower quality value, or a lossy format for photographic content.
Will the compressed PNG work everywhere?
Yes. Indexed PNG with alpha transparency is part of the PNG standard and is supported by all browsers, operating systems and design tools. WordPress, Shopify and other platforms accept the files without any special handling.